Boeing reportedly made the flight-control system that mistakenly activated during 2 deadly crashes 4 times stronger while creating the 737 Max

Boeing

A Boeing 737 Max.

• Boeing made a flight-control system that engaged during two deadly crashes stronger and more aggressive for its 737 Max aircraft, The New York Times reports.
• Boeing reportedly made the Maneuvering Characteristics Augmentation System (MCAS) four times stronger than when it was first sent to the Federal Aviation Administration (FAA) for review and increased the number of situations in which it would engage.
• The FAA knew about the changes Boeing made to MCAS but did not fully evaluate them, according to The New York Times report.
• "The change to MCAS didn't trigger an additional safety assessment because it did not affect the most critical phase of flight, considered to be higher cruise speeds," an FAA representative told Business Insider. "At lower speeds, greater control movements are often necessary."
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Boeing made a flight-control system that engaged during two deadly crashes stronger and more aggressive for its 737 Max aircraft, The New York Times reports.

In October, a Lion Air flight crashed and killed all 189 people on board, and in March, an Ethiopian Airlines flight crashed and killed all 157 people on board. The Maneuvering Characteristics Augmentation System (MCAS) activated due to false sensor readings on both flights.

Read more: Boeing's reputation has been stained by the 737 Max, and it's going to have to fight to convince people the plane is safe

Boeing reportedly made MCAS four times stronger than when it was first sent to the Federal Aviation Administration (FAA) for review and increased the number of situations in which it would engage. The FAA knew about the changes Boeing made to MCAS but did not fully evaluate them, according to The New York Times report.

Under the agency's rules, it reportedly did not have to launch a new review of the aircraft following the MCAS modification since it was not deemed to be of sufficient importance to the aircraft's operation. The agency ultimately assessed MCAS based on a prior version of the system that was less powerful and aggressive than the updated one.

"The change to MCAS didn't trigger an additional safety assessment because it did not affect the most critical phase of flight, considered to be higher cruise speeds," an FAA representative told Business Insider. "At lower speeds, greater control movements are often necessary."

Boeing told The New York Times that the FAA evaluated the final version of MCAS when it approved the 737 Max.

"The FAA considered the final configuration and operating parameters of MCAS during Max certification, and concluded that it met all certification and regulatory requirements," the company said.

Boeing did not immediately respond to Business Insider's request for comment.

MCAS points an aircraft's nose downward if the plane is flying at too steep an incline. Boeing installed the system on the 737 Max because the planes feature larger engines that are mounted in a different way from those on previous 737 aircraft. The new engines created a tendency for the 737 Max to tilt upward, which makes it more likely that the engines will stall in midair. The MCAS was designed to counter this tendency.

Boeing is working on software updates for the 737 Max that will involve MCAS.

• Read more:
• Boeing shareholders are suing the company, claiming it put safety at risk in a reckless pursuit of profits that ended in the 2 fatal 737 Max crashes
• Airlines have stopped buying Boeing 737 Max planes in the wake of the Ethiopian Airlines crash
• Lufthansa CEO reveals the biggest change in the airline industry caused by the Boeing 737 Max scandal
• Trump wants to put tariffs on $11 billion of EU goods, but doing so wouldn't be a 'new front in the trade war'

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